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GONDUGTOR FOB. ELEGTRIG RAILWJ AYS. No. 325,083. Patented Aug. 25, 1885.

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CONDUCTOR FOB. ELECTRIC RAILWAYS.

No. 325,083. Patented Aug. 25, 1885.

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CONDUCTOR FOR ELEOTRIG RAILWAYS. No. 325,083. Patented Aug. 25, 1885.

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5 Sheets-Sheet 4.

Patented Aug. 2-5, 1885.

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CONDUCTOR FOR ELECTRIC RAILWAYs.

No. 325,083. Patented Aug. 25, 1885.

IJNTTED STATES PATENT UFFI'CIEO JOHN HOPKINSON, OF IVFSTMINSTEB, COUNTY OF MIDDLFSEX, ENGLAND.

CONDUCTOR FOR ELECTRIC RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 325,083, dated August 25, 1885.

Applicaton filed March 9, 1885.

To all whom it may concern.-

Be it known that I, JOHN HOPKINSON, F. R. S., a subject of the Queen of Great Britain and Ireland, and residing at 4 "Westminster Chambers, Viestminster, in the county of MiddleseX, England, have invented certain Improvements in Electrical Railways and Tramways, (for which I have made application for a patent in Great Britain, No. 16,128, dated December 8, 1884,) of which the following is a specification.

My invention relates to an improved means of making the electrical connection between the generator and the motor in an electrical 1 railway or tramway of that class in which a wire or wires is suspended above the track, a

contact-piece on the car rolling or rubbing against the wire.

My invention consists in extending the contact pieces or rollers on the cars transversely to the car, so that the suspended conductor may occupy any position over the car laterally and contact still be maintained.

It also consists in placing'the contact-pieces on the cars at such a level that they will pass clear beneath the supports of the suspended wire without touching the same or lifting the wire from them.

The advantages of the overhead wire are, among others, that the conductor is placed out of reach and that mimltely-aceurate adj ustment is not needed, as the contactpiece on the car may lift the wires as the car travels along by nearly the full amount ofthe sag of the wire. a The peculiar advantages of my prcsentinvention are, that the distances between posts may be considerable, even on curves in the line, owing to the great freedom which arises from the lateral extension of the contacts on the car;

0 also, that since the contacts pass clear of the insulating-supports, these latter may be of a simple and inexpensive construction. The lateral extension of the contacts facilitates the working ofjunctions as well as of curves.

4 5 Referring to the drawings, Figure shows a side elevation of the conductor and car when the ear is between two posts. Fig. 2 is a similar view showing the car passing a post. Fig. 3 is an end elevation. Fig. 4is a side view of (No model.) Patented in England December F, 1894, No. 16,128.

a modified arrangement ofline-wires, and Figs. 5 and 6 are diagram plan views illustrating how my improvement comes into practical use.

The conducting-wire a (t is carried much as telegraphwires are carried; but special provision is made against the varying tension of the wires which arises from the passing cars lifting the wires aboveit. This may of course be effected by using posts fixed with exceptional strength; but when the spans are approximately equal it may be effected by allowing the wires to be free to slidelongitudinally when they are supported by the posts.

b b are the contact-pieces, extending across the width of the car and fixed in the case shown at a considerable height overhead, in order to be out of reach of passengers on the top of the car, and to leave headway under the wires where other roads cross. \Vhere these conditions do not exist, both conductors and contact-pieces may be placed lower. It will be observed that at least two contact-pieces are placed on the car, to enable the contact to be maintained when the car is passinga post, and this is necessary in my system, as the contactbars are at a lower level than the supports of the suspended wires.

The contactbars b b may be replaced by rollers to avoid friction and wear and tear; but in a similar way the rollers must be extended across the car to make contact at any point of its width.

I prefer to use at least two wires as the condoctor, in order to secure continuous contact even when the wires vibrate, and it is better to stretch them with a slightlydilferent tension, so that their normal times of vibration may be different: \Vhere great uniformity of contact is rcqui red, the number of posts is in creased and the wires are hung from alternate posts, as shown in Fig. 4.

It will be readily understood that a separate and similarly-insulated return-conductor may be provided; but I prefer to use the rails and the earth as return, as is well known. In that case the generating-dynamo has one pole con- 95 nected to the earth, the other to the insulated conductor a a, while the contacts I) 1/ are connected by a wire or other conductor to onepole of the dynamo placed on the car, the other pole of which is connected electrically to the wheels of the car and so to earth.

The electrical circuit is thus: generating dynamo, conductor a a, contacts I) I), motordynamo wheels of car, rails, earth, generating-dynamo.

Fig. 5 illustrates the application of my system to a curve. It will be observed that at X the bar I) b makes contact near one extremity, whereas at X it makes contact at the other extremity, but that the wires are not displaced laterally.

Fig. 6 illustrates the application to a junction of two lines. In this case,also,thelateral extension of the contact I) and its being placed 7 at a lower level than the supports of the wire enable the connection to be readily maintained at the junction.

It is unnecessary to describe orshow the an rangement of the dynamo on the car or the mechanisms for making or reversing the con ncctions thereof.

I claim as my invention-- l. The combination of the suspended conductor or conductors a a with the car carrying the contact bars or rollers 71 b, fixed to the car at such a level as to pass clear beneath the insulating-supports c c, and extending transversely across the car.

2. In electric tramways or railways, the combination of the suspended conductor or conductors with the car having a contact piece or surface or contact pieces or surfaces extended across the car, so that in all positions of the car proper contact with the Wires of the line is maintained, substantially as hereinbei'ore described.

In testimony whereof I have signed my name to this specification in the presence oftwo sub- 40 scribing witnesses.

JOHN HOPKIN SON.

Witnesses:

WM. JOHN WEEKs. CLAUDE WooDRoW.

Both of 31. Lombard lStrect, London. 

